1. If pq is odd, then p is odd and q is odd.

for this one, I had already proved that if p is odd and q is odd then pq is odd.

So in relation to this question i proved that q => p, so with a truth table I used that since p&q are the same(odd) then the reverse(p=>q) is also true.

does that sound alright?

2. if p^2 is even, then p is even.

This one im not quite sure how to prove ive tried the contrapositive:

so if p^2 is not even, the p is not even.

I substituted for p 2k+1, and tried setting it equal to 2k + 1 but my answer doesnt really make sense to me.

any help?